Kinetics of Droplet Growth in Liquid–Liquid Phase Separation of Polymer–Diluent Systems: Model Development

✍ Scribed by Kenneth S. McGuire; Anand Laxminarayan; D.Stefan Martula; Douglas R. Lloyd

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 256 KB
• Volume: 182
• Category: Article
• ISSN: 0021-9797
• DOI: 10.1006/jcis.1996.0435

✦ Synopsis

of this study was to model mathematically the droplet size A new model is presented for describing the increase in average as a function of the independent variables temperature, initial droplet size as a function of time for systems composed of diluent polymer concentration, and time for the model system isotacdroplets in a polymer-diluent matrix phase. The new model detic poly(propylene) -diphenyl ether. The equilibrium phase scribes the merging of any two droplets and accounts for the effect diagram reported elsewhere (1) was used to determine the that two coalescing drops has on neighboring drops. In particular, conditions under which liquid-liquid TIPS occurs.

as two drops coalesce, fluid is expelled from between them. This It has been reported that polymer-diluent systems underexpelled fluid causes the movement of neighboring drops, which going liquid-liquid phase separation show a strong depenleads to further coalescence of drops. The model predicts a strong dence of the droplet growth rate on the volume fraction influence of the droplet growth rate on the volume fraction of the droplet phase, which corresponds with experimental observations. of the droplet phase during the coarsening stages of phase The model was found to be sensitive to the matrix phase viscosity separation (2). Specifically, droplet diameter is proportional and the single fitting parameter, and less sensitive to the interfacial to time raised to some scaling exponent, where this scaling tension and Hamaker constant.